[clang] [MLIR] Update convert-gpu-to-spirv pass to prepare using GPU compilat… (PR #69941)

[Sang Ik Lee via cfe-commits]

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@@ -76,22 +76,24 @@ void GPUToSPIRVPass::runOnOperation() {
     // This works fine for Vulkan shader that has a dedicated runner.
     // But OpenCL kernel needs SPIRV module placed inside original GPU module as
     // OpenCL uses GPU compilation pipeline.
-    auto targetEnv = getTargetEnvFromGPUModuleOp(moduleOp);
+    const mlir::spirv::TargetEnv& targetEnv = getTargetEnvFromGPUModuleOp(moduleOp);
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silee2 wrote:

Removed mlir::

https://github.com/llvm/llvm-project/pull/69941